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The proper assessment of a client is a crucial component of personal training. Strength testing is an important tool used to determine muscular fitness, track progress, and identify muscle imbalances. As an exercise and health professional, you may choose the one-repetition maximum (1-RM) test as a baseline measurement to help a client set a strength-based goal. A client’s goals, abilities, and current fitness level will help you determine which test to utilize. For example, submaximal—or predicted 1-RM—strength testing is a great way to estimate 1-RM performance in a novice exerciser who does not have adequate experience handling free weights, whereas actual 1-RM testing will push the client to his or her limits and, therefore, is not appropriate for beginners. Because there is no single test that evaluates total-body strength, multiple tests are often necessary (e.g., bench press, leg press, and squat). Regardless of which assessment is used, a proper warm-up is always necessary to reduce injury risk and improve performance.

1-RM Assessment

Below is a step-by-step breakdown of how to perform a 1-RM assessment:

  • Perform a warm up and begin the first set with light resistance at 50% of anticipated 1-RM weight, staying between five to 10 repetitions.
  • Rest for one minute.
  • For the second set, increase the amount of weight to 70-75% of the anticipated 1-RM weight and decrease the number of repetitions to three to five.
  • Rest for one minute.
  • The third set should be performed at 85 to 90% of the anticipated 1 RM for two to three repetitions.
  • Rest for two to four minutes.
  • The information gained from the third set is then used to determine the workload for the client’s 1-RM effort. Using the information in Table 1, calculate an appropriate weight for the client’s 1 RM.

Example:

After warming up, your client performs a set of eight squats at 150 pounds, which represents roughly 80% of his or her 1 RM. To calculate the 1-RM trial, take the weight of the third set (150 pounds) divided by the percentage of 1 RM as determined in Table 1 to get a 1-RM trial weight of 187 pounds (150 lb /.80 = 187 lb). If a successful repetition is performed, allow the client to rest two to four minutes before attempting the 1-RM effort with a slight increase of roughly five to 10 pounds. If the repetition is unsuccessful, allow the client to rest two to four minutes before attempting the 1-RM effort with a slight decrease of roughly five to 10 pounds. This procedure should be repeated until the client achieves his or her 1 RM, ideally in fewer than five attempts.

Table 1

Percentage of 1 RM Based on Repetitions Completed

Repetitions

% 1 RM

1

100

2

95

3

93

4

90

5

87

6

85

7

83

8

80

9

77

10

75

11

70

12

67

15

65

Baechle, T.R. & Earle, R.W. (2008). Essentials of Strength Training and Conditioning (3rd ed.). Champaign, Ill.: Human Kinetics

 Predicted 1-RM Assessment

A predicted 1-RM test is a great way to estimate 1-RM performance in a novice exerciser who does not have adequate experience handling free weights. Table 2 provides the coefficients to calculate a predicted 1 RM based on the repetitions completed during an exercise set.

Table 2

1-RM Prediction Coefficients

Repetitions

Squat or Leg Press Coefficient

Bench or Chest Press Coefficient

1

1.00

1.00

2

1.0475

1.035

3

1.13

1.08

4

1.1575

1.115

5

1.2

1.15

6

1.242

1.18

7

1.284

1.22

8

1.326

1.255

9

1.368

1.29

10

1.41

1.325

Brzycki, M. (1993). Strength testing: Predicting a one-rep max from reps to fatigue. Journal of Physical Education, Recreation, and Dance, 64, 1, 88–90.

Apply What You Know

Now that you have determined your client’s 1 RM or predicted 1 RM, how do you use this information? Depending on your client’s goals, you can use his or her 1-RM weight to create a program that will lead to success. Table 3 lists the percentages of your client’s 1 RM and the repetition ranges associated with achieving specific training goals. For example, you are working with a client whose goal is to improve strength. You’ve determined that he has a 1-RM squat of 200 lb. Therefore, after warming up, during his squat workouts, he would need to perform six or fewer repetitions at or above 85% 1 RM (i.e., 170 lb) for his working sets to train for his goal of improving strength.

 Table 3

Recommended Training Volumes to Achieve Specific Goals

Training Goal

Repetitions

Intensity (% RM)

Strength Endurance

≥12

≤ 67 %

Hypertrophy

6–12

67–85%

Maximum Strength

≤ 6

≥ 85%

Power

· Single-repetition event

· Multiple-repetition event

 

1–2

3–5

 

80–90%

75–85%

 Baechle, T.R. & Earle, R.W. (2008). Essentials of Strength Training and Conditioning (3rd ed.). Champaign, Ill.: Human Kinetics; Westcott, W.L. (2003). Building Strength and Stamina (2nd ed.). Champaign, Ill.: Human Kinetics.

Increases in 1 RM can be very motivating for clients who wish to enhance their strength. In this regard, keeping records of 1-RM testing is a valuable strategy for tracking progress. Remember, 1-RM strength assessment is not appropriate for every client and it is the responsibility of the exercise and health professional to use proper judgment when selecting assessment techniques based on the client’s individual needs and goals.

 References

Baechle, T.R. & Earle, R.W. (2008). Essentials of Strength Training and Conditioning (3rd ed.). Champaign, Ill.: Human Kinetics.

Brzycki, M. (1993). Strength testing: Predicting a one-rep max from reps-to-fatigue. Journal of Physical Education, Recreation, and Dance, 68, 88–90.

Suggested Reading

 American Council on Exercise (2014). American Council on Exercise Personal Trainer Manual (5th ed.). San Diego, CA: American Council on Exercise.